Four-Year Outcomes of Cementless Versus Cemented Fixation of a Newly Introduced Total Knee Arthroplasty Design

Abstract

Background: Aseptic loosening continues to be a major cause of failure of total knee arthroplasty (TKA). Although cemented fixation remains the gold standard, there is renewed interest in cementless fixation as a means of decreasing this risk via biologic fixation. The purpose of this study was to evaluate the clinical outcomes of cemented and cementless versions of a newly introduced TKA design at an average of 4 years postoperatively. Materials and Methods: This was a retrospective case-control study of 100 primary TKAs comparing cementless vs cemented TKAs using the same cruciate-retaining implant design (ATTUNE Knee System; DePuy Synthes). Fifty patients undergoing cementless TKA with a mean age of 60.8 years (range, 48–71 years) and body mass index (BMI) of 31.6 kg/m 2 (range, 23.7–41.9 kg/m 2 ) were matched to 50 patients undergoing primary cemented TKA with a mean age of 62.7 years (range, 51–73 years) and BMI of 30.1 kg/m 2 (range, 24.6–43.9 kg/m 2 ). The mean follow-up was 4.2 years (range, 4.0–4.4 years) in the cementless group and 7.6 years (range, 7.5–7.7 years) in the cemented group. Complications, clinical outcomes using the Knee Society Score (KSS), and radiographic analyses were evaluated at final follow-up. Student's t tests were used for statistical analyses. Results: There was no statistical difference in age, BMI, and preoperative KSS between the two groups ( P =.12, P =.15, and P =.55, respectively). There were no complications or reoperations in either cohort. There were no statistical differences in range of motion and total KSS at final follow-up between the two groups. Final total KSS had a mean of 91.1 for the cementless group and 93.7 for the cemented group. There was no radiographic evidence of component subsidence or loosening in either cohort. Conclusion: When compared with its cemented counterpart, the newly introduced cementless TKA design had similar excellent clinical improvements and radiologic results at an average of 4 years of follow-up. [ Orthopedics . 202x;4x(x):xx–xx.]